Antistatic agent and resin composition and formed product

ABSTRACT

An antistatic agent characterized by containing a borate ester of polyoxyalkylene and an antistatic resin composition comprizing a thermoplastic resin and the borate ester of polyoxyalkylene and antistatic plastic resin formed product made by the plastic resin composition described above.

BACKGROUND OF THE INVENTION

[0001] 1. Field of the Invention

[0002] The present invent ion relates to an antistatic agent and an antistatic resin composition and an antistatic resin formed product.

[0003] 2. Description of the Related Art

[0004] Plastics have excellent properties such as easy processability, high productivity, light weight and relative low procuring cost, so they are used for the parts and structural materials for automobile, autobicycle, scooter, television, radio, audio equipment, washing machine, rice cooker, personal computer, portable telephone, game machinery, building materials office supplies, stationery, toys, sports goods, sports equipment, agricultural tools, marine tools, sheet and film.

[0005] They are usually prepared by plastic processing methods such as injection molding, blow molding, compression molding, transfer molding, rotating molding, slush molding, inflation tubular film process, and extrusion molding.

[0006] Plastic resins, especially polyethylene or polypropylene which has no polar group in the molecule are strong electrical insulating resistant, resulting to generate easily the static electricity when same or different plastic resins are rubbed, consequently they take an electrical charge.

[0007] And just then the plastic resin formed product take an electrical charge, they adsorb the dust in surrounding, resulting not only to make their appearance worse but also to give uncomfortable feeling when worker or user touch them.

[0008] Electrical charging sometimes becomes the cause of ignition and occasionally generates the trouble of production stop owing to the plastic resin formed product's surrounding to the processing machine at the production step.

[0009] Also, electrical charging of the plastic resin formed product gives bad influence when they are printed, painted or corona discharged.

[0010] As the preventing means for electrical discharging, there has been practised the methods such as coating the surface active agent on the surface of the plastic mold or plastic film; mixing the surface active agent by kneading into plastics; immersing the plastic product into the surface active agent solution; or spraying the surface active agent on the plastic product to be adhered.

[0011] There are many kinds of the surface active agent such as anionic, nonionic, cationic and amphoionic type.

[0012] Anionic type is inferior at compatibility with plastics and makes the plastics product's transparency worse.

[0013] Nonionic type has better compatibility with plastic than that of anionic type, however nonionic type gradually loses the antistatic effect according to the passing of time and nonionic type bleeds out from inside of the plastic to the surface of it to cause whitening of the surface, resulting to worse the product appearance.

[0014] Cationic and amphoionic type is inferior at heat resistance to cause colouring notwithstanding its good antistatic effect.

[0015] The above mentioned problems of each surface active agent are expected to improve.

[0016] An antistatic agent containing the organic boron compound is disclosed in the Japanese Laid-open Patent 4-252287, the organic boron compound which is obtained by reacting alcohol residual group containg compound having two adjacent hydroxyl group, with boric acid or borate ester.

[0017] The organic boron compound is pointed its defect of short durable terms of antistatic effect and whitening the surface of plastic molded product by bleeding of the organic boron compound.

SUMMARY OF THE INVENTION

[0018] As a result of diligent ivestigation by the present invention under such situation, the present invention provides an antistatic agent characterized by containing a borate ester of polyoxyalkylene, and an antistatic plastic resin composition, and an antistatic plastic resin formed product.

DETAILED DESCRIPTION OF THE INVENTION

[0019] A borate ester of polyoxyalkylene used for the present invention is a chemical compound expressed by the following general formula (1).

[0020] wherein R¹, R² and R³ are independently selected from group consisting of hydrogen and hydrocarbon group, a, b, c, d, e and f are positive integers independently from 0 to 30 whose sum is from 6 to 80.

[0021] Example of the hydrocarbon group are alkyl group such as methyl, ethyl, propyl, isopropyl, buthyl, penthyl, hexyl, octhyl, nonyl, decyl, dodecyl, hexadecyl, octadecyl and docosyl groups and phenyl, tolyl and cyclohexyl group.

[0022] Illustrative of the borate eater of polyoxyalkylene are the chemical compound expressed by the following chemical formula from (2) to (27).

[0023] Production method for borate esters of polyoxyalkylene used for the present invention are not limited to specific method, but following method is preferable.

[0024] The borate esters of polyoxyalkylene are produced by esteryfication-dehydration or ester-exchange reaction by contacting polyoxyalkylene expressed by the chemical formula (28) with boric acid or borate esters of lower alcohol such as methyl alcohol or ethyl alcohol.

[0025] It is prefavable that reaction is carried out by using 1 mol of boric acid or borate esters of lower alcohol with from 3 to 3.5 moles of polyoxyalkylene expressed by the chemical formula (28).

[0026] If the mole ratio is less than 3, it is not prefevable because undesirable byproducts of borate esters having two or three boron atoms are generated.

[0027] The other byproducts or unreacted polyoxalkylene may be remained in the borate esters unless they so not hinder the purging effect of the resin composition of the present invention.

R¹ (OCH₂CH₂) a (OCH₂CHCH₃) bOR²  (28)

[0028] wherein R¹ and R² are independently selected from group consisting of hydrogen and hydrocarbon group, a and b are independently from 0 to 30.

[0029] Example of the hydrocarbon group are alkyl group such as methyl, ethyl, propyl, isopropyl, buthyl, pentyl, hexyl, octyl, nonyl, decyl, dodecyl, hexadecyl, octadecyl and docosyl groups and phenyl, tolyl and cyclohexyl group.

[0030] Example of the polyoxyalkylene expressed by the chemical formula (28) are as follows.

[0031] diethylene glycol monomethyl ether,

[0032] diethylene glycol monoethyl ether,

[0033] diethylene glycol monoisopropyl ether,

[0034] diethylene glycol monobuthyl ether,

[0035] diethylene glycol monoocthyl ether,

[0036] diethylene glycol monodecyl ether,

[0037] diethylene glycol monohexadecyl ether,

[0038] diethylene glycol monooctadecyl ether,

[0039] triethylene glycol monomethyl ether,

[0040] triethylene glycol monoethyl ether,

[0041] triethylene glycol monoisopropyl ether,

[0042] triethylene glycol monobuthyl ether,

[0043] triethylene glycol monobuthyl ether,

[0044] triethylene glycol monoocthyl ether,

[0045] triethylene glycol monodecyl ether,

[0046] triethylene glycol monohexadecyl ether,

[0047] triethylene glycol monooctadecyl ether,

[0048] tetraethylene glycol monomethyl ether,

[0049] tetraethylene glycol monoethyl ether,

[0050] tetraethylene glycol monoisopropyl ether,

[0051] tetraethylene glycol monobuthyl ether,

[0052] tetraethylene glycol monoocthyl ether,

[0053] tetraethylene glycol monodecyl ether,

[0054] tetraethylene glycol monohexadecyl ether,

[0055] tetraethylene glycol monooctadecyl ether,

[0056] polyethylene glycol monomethyl ether,

[0057] polyethylene glycol monoethyl ether,

[0058] polyethylene glycol monoisopropyl ether,

[0059] polyethylene glycol monobuthyl ether,

[0060] polyethylene glycol monoocthyl ether,

[0061] polyethylene glycol monodecyl ether,

[0062] polyethylene glycol monohexadecyl ether,

[0063] polyethylene glycol monooctadecyl ether,

[0064] dipropylene glycol monomethyl ether,

[0065] dipropylene glycol monoethyl ether,

[0066] dipropylene glycol monoisopropyl ether,

[0067] dipropylene glycol monobuthyl ether,

[0068] dipropylene glycol monoocthyl ether,

[0069] dipropylene glycol monodecyl ether,

[0070] dipropylene glycol monohexadecyl ether,

[0071] dipropylene glycol monooctadecyl ether,

[0072] tripropylene glycol monomethyl ether,

[0073] tripropylene glycol monoethyl ether,

[0074] tripropylene glycol monoisopropyl ether,

[0075] tripropylene glycol monobuthyl ether,

[0076] tripropylene glycol monoocthyl ether,

[0077] tripropylene glycol monodecyl ether,

[0078] tripropylene glycol monohexadecyl ether,

[0079] tripropylene glycol monooctadecyl ether,

[0080] tetrapropylene glycol monomethyl ether,

[0081] tetrapropylene glycol monoethyl ether,

[0082] tetrapropylene glycol monoisopropyl ether,

[0083] tetrapropylene glycol monobuthyl ether,

[0084] tetrapropylene glycol monoocthyl ether,

[0085] tetrapropylene glycol monodecyl ether,

[0086] tetrapropylene glycol monohexadecyl ether,

[0087] tetrapropylene glycol monooctadecyl ether,

[0088] polypropylene glycol monomethyl ether,

[0089] polypropylene glycol monoethyl ether,

[0090] polypropylene glycol monoisopropyl ether,

[0091] polypropylene glycol monobuthyl ether,

[0092] polypropylene glycol monoocthyl ether,

[0093] polypropylene glycol monodecyl ether,

[0094] polypropylene glycol monohexadecyl ether,

[0095] polypropylene glycol monooctadecyl ether,

[0096] diethyleneglycol tripropyleneglycol monomethyl ether,

[0097] tetraethyleneglycol dipropyleneglycol monomethyl ether,

[0098] tetraethyleneglycol tripropyleneglycol monomethyl ether,

[0099] tetraethyleneglycol tetrapropyleneglycol monomethyl ether,

[0100] pentaethyleneglycol dipropyleneglycol monomethyl ether,

[0101] pentaethyleneglycol tripropyleneglycol monomethyl ether,

[0102] diethyleneglycol tetrapropyleneglycol monomethyl ether,

[0103] hexaethyleneglycol dipropyleneglycol monomethyl ether,

[0104] hexaethyleneglycol dipropyleneglycol monomethyl ether,

[0105] hexaethyleneglycol tripropyleneglycol monomethyl ether,

[0106] hexaethyleneglycol tetrapropyleneglycol monomethyl ether,

[0107] hexaethyleneglycol pentapropyleneglycol monomethyl ether,

[0108] hexaethyleneglycol hexapropyleneglycol monomethyl ether,

[0109] heptaethyleneglycol dipropyleneglycol monomethyl ether,

[0110] heptaethyleneglycol dipropyleneglycol monomethyl ether,

[0111] heptaethyleneglycol tripropyleneglycol monomethyl ether,

[0112] heptaethyleneglycol tetrapropyleneglycol monomethyl ether,

[0113] heptaethyleneglycol pentapropyleneglycol monomethyl ether,

[0114] heptaaethyleneglycol hexapropyleneglycol monomethyl ether,

[0115] heptaaethyleneglycol heptapropyleneglycol monomethyl ether,

[0116] octaethyleneglycol dipropyleneglycol monomethyl ether,

[0117] octaethyleneglycol tripropyleneglycol monomethyl ether,

[0118] octaethyleneglycol tetrapropyleneglycol monomethyl ether,

[0119] octaethyleneglycol pentapropyleneglycol monomethyl ether,

[0120] octaethyleneglycol hexapropyleneglycol monomethyl ether,

[0121] octaethyleneglycol heptapropyleneglycol monomethyl ether,

[0122] polyethyleneglycol polypropyleneglycol monomethyl ether,

[0123] triethylene glycol,

[0124] tetraethylene glycol,

[0125] pentaethylene glycol,

[0126] hexaethylene glycol,

[0127] heptaethylene glycol,

[0128] octaethylene glycol,

[0129] decaethylene glycol,

[0130] tridecaethylene glycol,

[0131] hexadecaethylene glycol,

[0132] eicosaethylene glycol,

[0133] pentacosaethylene glycol,

[0134] triacosaethylene glycol,

[0135] tripropylene glycol,

[0136] tetpropylene glycol,

[0137] pentapropylene glycol,

[0138] hexapropylene glycol,

[0139] heptapropylene glycol,

[0140] octapropylene glycol,

[0141] decapropylene glycol,

[0142] tridecapropylene glycol,

[0143] hexadecapropylene glycol,

[0144] eicosapropylene glycol,

[0145] pentacosapropylene glycol,

[0146] triacosapropylene glycol,

[0147] triethylene glycol tripropylene glycol,

[0148] tetraethylene glycol dipropylene glycol,

[0149] tetraethylene glycol tripropylene glycol,

[0150] tetraethylene glycol tetrapropylene glycol,

[0151] pentaethylene glycol dipropylene glycol,

[0152] pentaethylene glycol tripropylene glycol,

[0153] hexaethylene glycol dipropylene glycol,

[0154] hexaethylene glycol tripropylene glycol,

[0155] hexaethylene glycol pentapropylene glycol,

[0156] hepxaethylene glycol hexapropylene glycol,

[0157] heptaethylene glycol dipropylene glycol,

[0158] triacosaethylene glycol dipropylene glycol,

[0159] heptaethylene glycol tripropylene glycol,

[0160] heptaethylene glycol tetrapropylene glycol,

[0161] heptaethylene glycol pentapropylene glycol,

[0162] heptaethylene glycol hexapropylene glycol,

[0163] heptaethylene glycol heptapropylene glycol,

[0164] octaethylene glycol dipropylene glycol,

[0165] octaethylene glycol tripropylene glycol,

[0166] octaethylene glycol tetrapropylene glycol,

[0167] octaethylene glycol pentapropylene glycol,

[0168] octaethylene glycol hexapropylene glycol,

[0169] octaethylene glycol pentapropylene glycol,

[0170] octaethylene glycol octapropylene glycol,

[0171] polyethylene glycol polypropylene glycol,

[0172] tripropylene glycol triethylene glycol monomethyl ether,

[0173] tetrapropylene glycol diethylene glycol monomethyl ether,

[0174] tetrapropylene glycol triethylene glycol monomethyl ether,

[0175] tetrapropylene glycol tetraethylene glycol monomethyl ether,

[0176] pentapropylene glycol diethylene glycol monomethyl ether,

[0177] pentapropylene glycol triethylene glycol monomethyl ether,

[0178] pentapropylene glycol tetraethylene glycol monomethyl ether,

[0179] hexapropylene glycol diethylene glycol monomethyl ether,

[0180] hexapropylene glycol triethylene glycol monomethyl ether,

[0181] hexapropylene glycol tetraethylene glycol monomethyl ether,

[0182] hexapropylene glycol pentaethylene glycol monomethyl ether,

[0183] hexapropylene glycol hexaethylene glycol monomethyl ether,

[0184] heptapropylene glycol diethylene glycol monomethyl ether,

[0185] heptapropylene glycol triethylene glycol monomethyl ether,

[0186] heptapropylene glycol tetraethylene glycol monomethyl ether,

[0187] heptapropylene glycol pentaethylene glycol monomethyl ether,

[0188] heptapropylene glycol hexaethylene glycol monomethyl ether,

[0189] heptapropylene glycol heptaethylene glycol monomethyl ether,

[0190] octapropylene glycol diethylene glycol monomethyl ether,

[0191] octapropylene glycol triethylene glycol monomethyl ether,

[0192] octapropylene glycol tetraethylene glycol monomethyl ether,

[0193] octapropylene glycol pentaethylene glycol monomethyl ether,

[0194] octapropylene glycol hexaethylene glycol monomethyl ether,

[0195] octapropylene glycol heptaethylene glycol monomethyl ether

[0196] octapropylene glycol octaethylene glycol monomethyl ether

[0197] polypropylene glycol polyethylene glycol monomethyl ether

[0198] tripropylene glycol triethylene glycol monomethyl ether,

[0199] tetrapropylene glycol triethylene glycol monomethyl ether,

[0200] tripropylene glycol triethylene glycol monomethyl ether,

[0201] octapropylene glycol diethylene glycol monomethyl ether,

[0202] octaethylene glycol dipropylene glycol monomethyl ether,

[0203] octaethylene glycol tripropylene glycol monomethyl ether,

[0204] octaethylene glycol tetrapropylene glycol monomethyl ether,

[0205] octaethylene glycol pentapropylene glycol monomethyl ether,

[0206] octaethylene glycol hexapropylene glycol monomethyl ether,

[0207] octaethylene glycol heptapropylene glycol monomethyl ether,

[0208] octaethylene glycol octapropylene glycol monomethyl ether,

[0209] polyethylene glycol polypropylene glycol monomethyl ether.

[0210] A solvent or diluent may be incorporated into the raw materials such as boric acid, borate ester of lower alcohol and polyoxyalkylene, or into borate esters of glycol ether.

[0211] If the solvent or diluent are employed, they must not disturb the esteryfication-dehydration or ester-exchange reaction and their boiling point are preferable bellow the boiling point of the byproducts or polyoxyalklenes.

[0212] Example of the solvent or diluent are ethers such as diethyl ether, dioxane, tetrahydrofran; aliphatic hydrocarbons such as hexane, acetic anhydride, heptane, octane, nonane, decane, undecane; aromatic hydrocarbons such as benzene, toluene, xylene; cycloalkane such as cyclohexane, cyclohexene; non-proton polar compound such as dimethy formamide, dimethyl sulfoxide, hexamethyl polyamide phosphate, acetonitrile, N-methyl pyrrolidone; and their chlorine substituted compound such as chloroform and carbon tetrachloride.

[0213] A catalysts for the esteryfication-dehydration or ester-exchange reaction may be used.

[0214] If the catalysts are necessary for promoting the reaction, following condensation catalysts are recommended.

[0215] Example of the catalysts are metallic salt of organic acid such as ferrous octanoate, ferrous naphthenate, cobaltous naphthenate, manganese octanoate, stannum octanoate, stannum naphthenate, lead octanoate, lead naphthenate, organotin compound such as dibuthy tin diacetate, dibuthyl tin dioctanoate, dibutly tin dilaurate, dibutyl tin dioleate, dibutyl tin dimethoxide, oxidized dibutyl tin; metal alcoholate such as tetrabuthyl titanate, tetrabutyl zirconate; titanium chelate such as di-isopropoxy bis-acetyl acetonate titanium, 1,3-propanedioxy bis-ethylacetonate titanium, 1,3-propanedioxy bis-ethylacetoacenate titanium; alminum chelate such as alminum acethylacetonate, alminum tris-ethylacetoacetonate; amines such as hexyl amine, dodecylamine phosphate, dimethyl hydroxyamine, diethyl hydroxyamine; tetra-ammonium salt such as benzyl hydroxyamine; inorganic acid such as hydrochlonic acid, nitric acid, sulfric acid, phosphoric acid; organic acid such as acetic anhydride, pure acetic acid (over 99.8%), propionic acid, citric acid, benzoic acid, formic acid, acetic acid, oxalic acid, p-toluenesulfonic acid; chlorosilane such as methyl tri-chlorosilane, dimethyl di-chlorosilane; inorganic base such as aqueous ammonia; organic base such as ethylene diamine, tri-ethanol amine; and amino alkylamine.

[0216] It is preferable that the esteryfication-dehydration ester-exchange reaction is carried out under the condition of at reduced or atmospheric pressure from 50 to 250° C. temperature, favourably from 100 to 180° C.

[0217] Under the reaction, removal of byproducts such as lower alcohol or water can proceed the reaction easily because removal of byproducts proceed the reaction equilibrium to favorable direction of borate ester of polyoxyalkylenes formation.

[0218] As to the removal method, azeotropic distillation using azeotropic agent and batch or continuous distillation using distillation tower are preferable.

[0219] For the purpose of improving the properties of the borate ester of polyoxyalkylenes, amino group containing compound and/or solvent may be added to said borate esters of polyoxyalkylenes.

[0220] Adding the amino group containing compound to the borate ester of polyoxyalkylenes exhibits the suppressing of borate ester hydrolysis and also exhibits rust preventive effect under the condition of existense of water or its vapor.

[0221] Examples of the amino-group containing compound include alkylamine, cyclo alkyl amine, alkanol amine, heterocyclic amine, diamine, lactam, cyclic imide and polyamine, which may be used alone or combination selecting from these compound.

[0222] As the alkyl amine, there can be used methyl amine, dimethyl amine, trimethyl amine, ethyl amine, diethyl amine, triethyl amine, propyl amine, N,N-di[poly (4) oxyethyl] hexadecyl amine, dodecyl dimethyl amine, stearamide propyl dimethyl amine, polyoxyethylene (3-30) octadecyl amine, polyoxyethylene (3-30) laurylamine, polyoxethylene (3-30) oleyl amine, polyoxyethylene (3-30) dilauryl amine, polyoxyethylene (3-30) stearyl amine, polyoxyethylene (3-30) alkylamine, polyoxyethylene 3-30) dialkyl amine, and di (oleoyloxyethyl) hydroxy amine.

[0223] As the cycloalkyl amine, there can be used cyclohexyl amine, methyl cyclohexyl amine and ethyl cyclohexyl amine.

[0224] As the alkanol amine, there can be used ethanol amine, diethyl hydroxy methyl amine, diethanol amine, dimethyl aminoethanol, triethanol amine, propanolamine, dimethy 2-hydroxypropyl amine, buthanol amine, methyldi(2-hydroxyethyl) amine, tri(2-hydroxyethyl)amine, hydroxymethyl di(2-hydroxyethyl)amine, dibenzil 2-hydroxypropyl amine and cyclohexyl di(2-hydroxyethyl) amine.

[0225] As the cycloalkanol amine, there can be used cyclohexanol amine, methylcyclo hexanol amine and ethylcyclohexanol amine.

[0226] As the heterocyclic amine, there can be used used pyridine, lutidine, 3,4-xylidine, piperidine, N-methyl piperidine and N-ethyl piperidine.

[0227] As the lactam, there can be used proio lactam, N-methylpropyo lactam, N-ethyl buthyro lactam, N-methyl varero lactam, N-methyl caprolactam and phenyl caprolact am.

[0228] As the cyclic imide, there can be used succinimide, N-methyl succinimide, N-ethyl succinimide, phenyl succinimide and 2-undecyl imidazoline.

[0229] As the diamine, there can be used ethylene diamine, triethylene diamine and tetraethylene diamine.

[0230] As the polyamine, there can be used diethylene triamine, triethylene tetramine and pentaethylene pentamine.

[0231] Among these aminogroup containing compound, tertiary aminogroup containing compounds exhibit excellent effect of preventing hydrolysis of borate ester of polyoxyalkylene and promoting the cleaning and purging the coloured contaminants.

[0232] Example of tertiary aminogroup containing compounds having above mentioned excellent properties are polyoxyethylene (3-30) octadecyl amine, polyoxyethylene (3-30) laurylamine, polyoxyethylene (3-30) oleyl amine, polyox-yethylene(3-30) dilauryl amine, polyoxyet-hylene (3-30) stearyl amine, polyoxyethyl-ene (3-30) alkylamine, polyoxyethylene (3-30) dialkyl amine and di(oleoyloxyethyl) hydroxy amine.

[0233] The amount of aminogroup containing compound to 100 parts by weight of borate ester of polyoxyalkylene is from 0 to 100 parts by weight, favourably from 5 to 50 parts by weight and most fovourably from 10 to 30 parts by weight.

[0234] Use of the solvent contributes to lower viscosity of the borate ester of polyoxyalkylene.

[0235] As the solvent, there can be used water, methyl alcohol, ethyl alcohol, is opropyl alcohol, butyl alcohol, isopropyl ether, ether, ethylene glycol, polyethylene glycol, polyethylene dimethyl ester, diethylene glycol, triethylene glycol, ethylene glycol dimethyl ether, diethylene glycol dimethy ether, diethylene glycol diethy ether, ethylene glycol dipropyl ether, triethylene glycol dimethyl ether, triethylene glycol monobuthyl ether, diethylene glycol monobutyl ether, diethylene glycol diethyl ether, diethylene glycol propyl ether, diethylene glycol dibuthyl ether, dimethyl ether, propylene glycol, acetone, methyethyl ketone, furfural, dioxane, methane sulfonate, diethy ether, tetra hydrofuran, hexane, acetic anhydride, heptane, octane, nonane, decane, undecane, benzene, toluene, xylene, cyclohexane, cyclohexene, dimethyl formamide, dimethy sulfoxide, hexamethyl triamide phosphate, acetonitrile, N-methyl pyrrolidone, chloroform and carbon tetrachloride and the solvents are used by alone or combination.

[0236] The amount of solvent to 100 parts by total weight of borate ester of polyoxyalkylene and aminogroup containing compound are from 0 to 100 parts by weight, favourably from 5 to 50 parts by weight and most favourably from 10 to 30 parts by weight.

[0237] The other ingredient other than aminogroup containing compound and/or solvent may be incorporated to borate ester of polyoxyalkylene for the purpose of improving the properties of cleaning and purging resin compound of the present invention.

[0238] As the other ingredient, there can be used stabilizer, neutralizer, antioxidant, ultraviolet absorber, light stabilizer, antistatic agent, lubricant, processability improving agent, filler, dispersing agent, coupling agent, anticopper rusting agent, blowing agent, nuclear forming agent, antiforming agent, deformer, colourant, pigment, dyeing agent, carbon black, water tree preventing agent, voltage stabilizer, antitracking agent, organic peroxide, crosslinking agent, disinfectant, antiseptics, antimold agent and antirust agent.

[0239] The antistatic agent of the present invention is a chemical compound having the function to prevent following problems.

[0240] One problem is that the dusts in surrounding near the plastic resin formed product are adsorbed on that, resulting not only to make their appearance worse but also to give uncomfortable feeling when worker or user touches that.

[0241] The other problem is electrical charging to cause of ignition or production stopping, which is caused by that the plastic resin formed product surrounds to the parts of a processing machine at the production step.

[0242] Another problem is giving bad influence at surface treating of the plastic product such as printing, painting or corona discharging.

[0243] The antistatic agent of the present invention is prepared using one or more than one kind of borate ester of polyoxyalkykene.

[0244] The antistatic agent may contain amino group containing compound and/or solvent.

[0245] The antistatic agent may further contain surface active agent, pigment, dye, inorganic filler, dripping preventable agent, precipitation preventable agent, antioxidant and deformer.

[0246] The antistatic agent may be filled in the aerosol container with propellant.

[0247] Coating of the antistatic agent of the present invention on the surface of the plastic molded product, plastic film, machine part, apparatus or process machine can be conducted by brushing, spraying, dipping of the antistatic agent; or contacting woven cloth or nonwoven cloth which are immersed with the antistatic agent onto the surface of the plastic molded product, plastic film machine part, apparatus and process machine.

[0248] The antistatic agent of the present invention can be heat kneaded into plastic resin to form antistatic plastic resin composition.

[0249] The antistatic plastic resin composition can be formed by plastic processing machine to obtain plastic film, sheet, bottle and container having antistatic property.

[0250] The plastic resin used for the plastic resin composition of present invention is the thermoplastic resin.

[0251] As the thermoplastic resin, there can be used high density polyethylene, high pressure low density polyethylene such as HP-LDPE, EVA, EEA, Ionomer, olefin vinylalcohol copolymer, LLDPE, VLDPE, polypropylene (PP), polystylene (PS), acrylonitrile-butadiene-stylene copolymer (ABS), acrylonitrile-stylene copolymer (AS), acrylonitrile-butadiene copolymer, acrylonitrile acrylate-stylene copolymer, polyvinyl chloride (PVC), polyamide, polymethylmethacrylate (PMMA), polyacetal (POM), aminopolyacrylamide, polyarylate, fluoro carbon resin, polyimide (PI), polyaminobismaleimide (PABI), polyamideimide (PAI), polyetherimide (PEI), bismaleimidetriazine resin (BT), polysulfone, polybutylene terephthalate (PBT), polyethylene terephthalate (PET), polyvinylidend chloride, polycarbonate (PC), polyvinyl acetate, polyvinyl alcohol, polyvinyl ether, polyvinyl formale, modified PPE, modified polyphenyleneoxide (PPO), polyphenylene sulfide (PPS), polyethersulfone (PESF), polyetheretherketone (PEEK), polyarysulfone (PAS), polymethylpenten (TPX), liquid crystal polymer, silicone resin, natural rubber (NR), butyl rubber (I IR), acrylonitrile butadiene rubber (NBR), chloroprene rubber (CR), styrene butadiene rubber (SBR), butadiene rubber (BR) and the like.

[0252] Production method of the antistatic resin composition is not limited to specific method, however following method is desirable.

[0253] To the 100 parts by weight of a themoplastic resin, 0.1˜10 parts by weight of a borate ester of glycol ether expressed by general formula (1) is added.

[0254] The form of the thermoplastic resin may be powder or pellet form.

[0255] The borate ester of polyoxyalkylenes may be soaked into thermoplastic resin powder or pellet.

[0256] The soaking is desirable to conduct at the temperature of over the glass transition point because at the temperature soaking speed is fast.

[0257] The other production method for the antistatic resin composition of the present invention may be conducted as follows.

[0258] The thermoplastic resin and borate ester of polyoxyalkylenes are fed to plastic processing machine or bunbury mixer, in which they are blended and extruded from pelletizing die havinng many hole of 3˜7 mm diameter.

[0259] Each extruded strings are cut to form pellet having the length of 3˜7 mm.

[0260] In case the amount of the borate ester of polyoxyalkylenes is less that 0.1 parts by weight, the resin composition for purging does not exhibit the cleaning and perging effect and in case more than 10% parts by weight, it is not desirable because the uniform polymer blend is barely obtained.

EXAMPLE

[0261] Now, an antistatic agent characterized by containing a borate ester of polyoxyalkylene, and an antistatic plastic resin composition, and an antistatic plastic resin formed product according to the present invention will be described in further detail with reference to Example.

[0262] However, it shoud be understood that the present invention is by no means restricted by such specific Example.

Example 1

[0263] Borate ester of polyoxyalkylenes expressed by chemical formula (12) was obtained by following synthesis process.

[0264] In a 7000 ml flask equipped with three inlet pipe and displaced by nitrogen gas were charged 146 g (1 mole) of triethyl borate [B(OC₂H₅)₃], 1.2 g of dibutyl tin dilaurate and 50 ml of benzene.

[0265] Subsequently, the solution in the flask was added with 1796 g (2 mole) of eicosaethylenglycol and 912 g (1 mole) of eicosaethylenglycol monomethyl ether under stirring condition to obtain uniform blended solution.

[0266] Subsequently, the solution in the flask was stirred for 13 hours at 95° C. under the condition of distillation to remove a ethanol and benzene as the byproduct to obtain 2716 g (0.99 mole) of a borate ester of polyoxyalkylenes expressed by chemical formula (12).

[0267] Also, the other borate ester of polyoxyalkylenes expressed by chemical formula (23) was obtained by following synthesis process.

[0268] In a 7000 ml flask equipped with three inlet pipe and displaced by nitrogen gas were charged 2264 g (2 mole) of pentacosa ethyleneglycol and 242 g (1 mole) of pentadecanol under stirring condition to obtain uniform blended solution.

[0269] Subsequently, the solution in the flask was stirred for 13 hours at 95° C. under the condition of distillation to remove a ethanol and benzen as the byproduct to obtain 2514 g (0.99 mole) if a borate ester of polyoxyalkylenes expressed by chemical formula (23).

[0270] Then, an antistatic agent (1) consisting 50 parts by weight of borate ester of polyoxyalkylenes expressed by chemical formula (12) and 50 parts by weight of borate ester of polyoxyalkylenes expressed by chemical formula (23) and 15 parts by weight of triethylamine was prepared by mixing the above three components.

[0271] In a vessel, 100 parts by weight of high pressure low density polyethylene (made by Nippon Unicar Company Ltd., melt mass flow late 10.0 g/10 min., density 0.92 3 g/cm³) and 0.2 parts by weight of the antistatic agent (1) obtained by above mentioned method were blended for 5 minutes under room temperature to obtain mixture, then the mixture was thrown into the continuous blending extruder (made by K.C.K. Company Ltd., machine name K.C.K 80X2-35 VEX type) under condition of cylinder temperature of 190° C. to produce the resin composition as a pellet form having length of 3 mm and diameter of 3 mm.

[0272] The resin composition was named hearafter antistatic resin composition (1).

[0273] Then tubular film having 50 μm thickness was prepared using antistatic resin composition (1) by air cooling inflation film processing machine.

[0274] The tubular film was named hearafter antistatic tubular film (1).

[0275] Subsequently, the antistatic effect evaluation test was conducted by following procedures.

[0276] The tubular film (1) was left on the table under the conditions of 23° C. temperature and 50% RH (Relative Humidity) for three days, then the surface resistivity for the tubular film (1) was measured according to Japanese Industrial Standard K 6911 to find 7.21×10¹¹Ω resistivity for outer surface and 1.28×10¹²Ω resistivity for inner surface, which are excellent value comparing to that of comparative example 1 as shown below.

[0277] The half-life of electrostatic voltage for the tubular film (1) was measured according to Japanese Industrial Standard L1094 to find 1.43 sec. for outer surface of the film and 1.92 sec. for inner surface of the film, which are excellent value comparing to that of com parative example 1 as shown below.

[0278] When 30 days had passed from the day that resistivity and half-life of electrostatic voltage were measured, the same tests were conducted to find 9.75×10¹¹Ω resistivity for outer surface and 4.08×10¹²Ω resistivity for inner surface, which were excellent value comparing to comparative example and to find 2.51 sec. half-life of electrostatic voltage for outer surface and 3.11 sec. half-life of electrostatic voltage for inner surface, which was excellent value comparing to that of comparative example 1 as shown below.

Comparative Example 1

[0279] As an example of conventional type antistatic agent (2), 2 mol etyleneoxide added stearylamine was prepared.

[0280] In a vessel, 100 parts by weight of high pressure low density polyethylene (made by Nippon Unicar Company Ltd., melt mass flow late 10.0 g/10 min. density 0.923 g/cm³) and 0.2 parts by weight of conventional type antistatic agent (2) were blended for 5 minutes under room temperature to obtain mixture, then the mixture was thrown into the continuous blending extruder (made by K.C.K. Company Ltd., machine name K.C.K 80X2-35 VEX type) under condition of cylinder temperature of 190° C. to produce the resin composition as a pellet form having length of 3 mm and diameter of 3 mm.

[0281] The resin composition was named hearafter antistatic resin composition (2).

[0282] Then tubular film having 50 μm thickness was prepared using antistatic resin composition (2) by air cooling inflation film processing machine.

[0283] The tubular film was named hearafter antistatic tubular film (2).

[0284] Subsequently, the antistatic effect evaluation test was conducted by following procedures.

[0285] The tubular film (2) was left on the table under the condition of 23° C. temperature and 50% RH (Relative Humidity) for three days, then the surface resistivity for the tubular film (2) was measured according to Japanese Industrial Standard K 6911 to find 8.65×10¹¹Ω resistivity for outer surface and 2.45×10¹²Ω resistivity for inner surface, which was inferior value comparing to that of example 1 as shown above.

[0286] The half-life of electrostatic voltage for the tubular film (2) was measured according to Japanese Industrial Standard L 1094 to find 9.45 sec. for outer surface and 10.87 sec. for inner surface, which was inferior value comparing to that of example 1 as shown above.

Example 2

[0287] Borate ester of polyoxyalkylenes expressed by chemical formula (8) was obtained by following synthesis process.

[0288] In a 7000 ml flask equipped with three inlet pipe and displaced by nitrogen gas were charged 146 g (1 mole) of triethyl borate [B(OC₂H₅)₃], 1.2 g of dibutyl tin dilaurate and 50 ml of benzene.

[0289] Subsequently, the solution in the flask was added with 756 g (3 mole) of pentylethylenglycol monomethyl ether under stirring condition to obtain uniform blended solution.

[0290] Subsequently, the solution in the flask was stirred for 13 hours at 95° C. under the condition of distillation to remove a ethanol and benzene as the byproduct to obtain 758 g (0.99 mole) of a borate ester of polyoxyalkylenes expressed by chemical formula (8).

[0291] Then, an antistatic agent (3) consisting 1 parts by weight of borate ester of polyoxyalkylenes expressed by chemical formula (8) and 1 parts by weight of polyoxyethylene (9) lauryl amine were prepared by mixing the above two components.

[0292] In a vessel, 100 parts by weight of high pressure low density polyethylene (made by Nippon Unicar Company Ltd., melt mass flow late 10.0 g/10 min., density 0.92 3 g/cm³) and 0.2 parts by weight of the antistatic agent (3) obtained by above mentioned method were blended for 5 minutes under room temperature to obtain mixture, then the mixture was thrown into the continuous blending extruder (made by K.C.K. Company Ltd., machine name K.C.K 80X2-35 VEX type) under condition of cylinder temperature of 190° C. to produce the resin composition as a pellet form having length of 3 mm and diameter of 3 mm.

[0293] The resin composition was named hearafter antistatic resin composition (3).

[0294] Then tubular film having 50 μm thickness was prepared using antistatic resin composition (3) by air cooling inflation film processing machine.

[0295] The tubular film was named hearafter antistatic tubular film (3).

[0296] Subsequently, the antistatic effect evaluation test was conducted by following procedures.

[0297] The tubular film (3) was left on the table under the condition of 23° C. temperature and 50% RH (Relative Humidity) for three days, then the surface resistivity for the tubular file (3) was measured according to Japanese Industrial Standard K 6911 to find 5.78×10¹¹Ω resistivity for outer surface and 0.97×10¹²Ω resistivity for inner surface, which were excellent value comparing to that of example 1.

[0298] The half-life of electrostatic voltage for the tubular film (3) was measured according to Japanese Industrial Standard L 1094 to find 1.18 sec. for outer surface and 1.76 sec. for inner surface, which were excellent value comparing to that of example 1.

[0299] When 30 days had passed from the day that resistivity and half-life of electrostatic voltage were measured, the same test were conducted to find 7.67×10¹¹Ω resistivity for outer surface and 3.89×10¹²Ω resistivity for inner surface, which were excellent value comparing to example 1 and to find 2.12 sec. half-life of electrostatic voltage for outer surface and 2.69 sec. half-life of electrostatic voltage for inner surface, which were excellent value comparing to that of example 1.

[0300] The experiment result showed that the antistatic agent of the present invention had excellent property that its surface resistivity was low value and its half-life of electrostatic voltage was short time.

[0301] Low surface resistivity of the plastic film means that the plastic film will hardly be charged with static electricity, resulting that the plastic film will not adsorb the dust in the surrundings.

[0302] Short half-life of electrostatic voltage means that the durable term of the antistatic effect of the plastic film is long.

[0303] Also, the surface of the plastic film made by the resin compound of the present invention does not show sticky touch feeling. 

What is claimed is:
 1. An antistatic agent characterized by containing a borate ester of polyoxyalkylene expressed by the following general formula (1)

wherein R¹, R² and R³ are independently selected from group consisting of hydrogen and hydrocarbon group, a, b, c, d, e and f are positive integers independently from 0 to 30 whose sum is from 6 to
 80. 2. An antistatic agent according to claim 1, which further comprising amino group containing compound.
 3. An antistatic plastic resin composition characterized by comprizing (A) 100 parts by weight of a thermoplastic resin (B) 0.1-10 parts by weight of an antistatic agent described in claim
 1. 4. An antistatic plastic resin composition according to claim 3, which further comprising (C) 0.1-10 parts by weight of amino group containing compound.
 5. An antistatic plastic resin formed product made by said plastic resin composition described in claim 3 or
 4. 